James bibby



Aug. 26 1924. Re. 15,903 J. BIBBY POWER 'rnmsnssiou GOUPLIIG- OriginalFiled Dec. 14. 1820 INVENTOR.

.Imzs .B/BB Y BY ATTORNEY.

. ject of the King of ReiauedAug.26, 1924.

UNITED STATES PATENT OFFICE.

sums many, or LONDON, ENGLAND.

rowna-rnmsmssrou courLmG.

original Io. 1,881,718, dated September 27, 19 21, Serial No. 430,709,filed December 14, 1920. Application tor reiuue med Kay 2, 1923. SerialNo. 636,258.

To all'wlwm it may com-em:

Be it known-that I, James BIBBY, a sub- Great Britain, residing atLondon, in the county of Middlesex, England, have invented new anduseful Improvements in Power-Transmission Coulings, ofwhich thefollowing is a speciiication.

This invention relates to couplings used to transmit power from adriving member to a driven member such, as two co-a-xial lengths ofshaft. In couplings of this kind i to that of flexibility.

it is often necessary to have a certain amount of flexibility toaccommodate unavoidable eccentricity and lack of alinement of theshafts.It is also necessary to provide sufliciently strongetransmitting orinterconnecting means tween the elements of the coupling to withstandall possible overload torques. In practice it is found that theseoverload torques may momentarily be of the order of 500 per cent of'thenormal load owin to sudden accelerations, retardations, fly wheeleffects, obstructions in the driven machines, and so forth, and hithertoit has been necessary to make so much allowance for these overloads thatthe coupling is unduly stiif for normal loads and as a shock absorbingcapacity for such loads only a fraction of w were designed for normalloads only. It follows therefore that a flexible couplin which is ableto damp the transmitting torsional shocks has an additional advantageThe chief object of the present invention is to provide a couplinghaving these advantages possessing stren h to transmit overloa torquesand full exibilit mal and even su -normal loads. Further advanta es ofthe improved coupling are hereinafer referred to.

According to the present invention the colcilpling comprises elements onthe driving an driven members respectively and flexible interconnectimeans of grid form affording adequate exibility for normal and evensub-normal loads and increasin resistanoe to distortion with increase 0distoltion due to increase of transmitted torque. Co uently within widelimits the stren h o the coupling is'not materially ecreased by increaseof load.

In the preferred constructional form of this compensating coupling thetwo elements I of the rods at it would be if the coupling v andresilience for northereof on the driving and driven members shaped thatthe more the rods become de- Y fiected the shorter becomes theirunsupported length. These rods are connected together by end pieces soas to constitute a continuousrod of zig-zag or grid form for whichpurpose a stout wire may be bent to and fro. It will be understood thatin order to insure a maximum unsu ported length of the rods atno loadand a decreasing unsupported length with increasing load, the alinedgaps or grooves, in the coupling elements will be only sufliciently wideat their remote ends to house the ends but will increase in widthprogressively toward their abutting or adoining ends. The curvature orflared formation of the side walls of these grooves is modified ascurvature of the rods in their condition of maximum deflection, theircurvature bein sharper so that as the rods become deflected theirunsupported lengths become less.

The invention will now be described more fully with reference to thepreferred embodiment illustrated in the accompanying drawings.

The upper half of Fi tudinal elevation partly lower half being a lon'tudinal section. Fig. 2 is an exaggerated etail view.

1 and 2 are the driving and driven members respectively and 3 and 4respectively are the cou ling elements thereon. The peripheries o theelements 3 and 4 have normally alined axially directed grooves 5 and 6equally s aced and communicating at their remote en s withcircumferential channels 7 and 8. The interconnecting means be tween theelements 3' and 4 are constituted by the flexible rods 9 formin theparallel limbs of a id-like sprin stee wire. These rods 9 lie in thenormal y alined grooves 5 and 6 and the curved connectin pieces 10 liein the channels 7 and 8. e grooves are just wide enough at their remoteends to accommodate the rods 9 and are flared inwardly, the side wallsbein curved as shown so that when power is ing transmitted and thegrooves become out of alineroken away, t 0

compared with the natural ml is a longlp,

' interconnecting grid ment, the unsupported lengths of the rodsdecrease proportionally with the deflection, as shown in Fig. 2. Inother words, the shape of the side walls of the grooves is such that asthe two cou ling elements become angularly displace more and more, sothat the deflection of the rods 9 brings them more and more in contactwith the side walls and the unsupported lengths of the rods become lessand less and their bendin moments reduced, the limit being attamed whenpractically the full lengths are supported, beyond which the resistancewill approach that opposed to shear. Under normal loads, however, aconsiderable length of the rods will be unsupported and consequentlythere will be a great capacity to absorb shocks.

Further features of novelty incidental to the construction illustratedare of practical importance. It is to be noted that both couplingelements are practically identical and cooperate at their eriphery withthe interconnecting rods an thus produce their maximum effect owing tothe maximum leverage of both elements as distinguished from existingtypes of coupling where one at least 1 of the coupling elementsisengaged at some distance inwardly from its periphery. Hence, for thesame torque-transmission this novel form of coupling requires a lessdiameter than existing forms.

Moreover, the transmission by way of the roduces no couple in a radialdirection. onsequently no provision has to be made .for restrainingradial forces as in existin types of couplings, and only a light cylinrical casing 11 need be fitted to serve as a retainer of lubricant.

It will be seen that this coupling works equally well in eitherdirection.

What I claim and desire to secure by Let ters Patent is:

1. A flexible shaft couplin com rising two coupling elements arrangedside y side on the driving and driven shafts respectively and agrid-like interconnecting member havin its parallel limbs extendinglongitudihaving normally na ly in normally alined rooves in saldelements, the walls of sai rooves being so shaped that the more the imbsbecome deflected by relative angular movement between the elements dunngtorque transmission the less becomes their unsupported length.

2. A flexible shaft coupling comprising two-coupling elements side byside on the driving and driven shafts respectively and alined inwardlyflaring grooves extendmg longitudinally, and a rid-like interconnectingmember the paralel limbs of which lie in the aforesaid grooves.

I 3. A flexible shaft couiplin'g comprising two coupling elements 'si eby side on the driving and driven shafts respectively and havingnormally alined inwardly aring grooves extending longitudinally in theirperipheries and a spring steel stout wire in grid form the parallellimbs of which are housed in the aforesaid grooves.

4. A flexible shaft coupling comprising coupling elements side by'sideon the driving and driven shafts respectively and having peripheralaxially directed and normally alined inwardly flaring grooves therein, aspring steel stout wire of rid form having its parallel limbs house insaid grooves and a light cylindrical casing inclosing said elementsperipherally.

5. A flexible shaft coupling comprising coupling elements on the drivingand driven shafts respectively and having peripheral axially directedand normally alined inwardly flaring grooves, a grid-likeinterconnecting member housed in said grooves, the walls of the latterbeing modified as compared with the natural curvature of the parallellimbs of said member in their maximum deflected condition so that as thelimbs become dcflected their unsupported length becomes ess.

6. A flexible shaft coupling comprising two coupling elements side byside on the driving and driven shafts, respectively, each having acircular series of grooves, and a grid-like interconnecting membercomprising a series of transversely resilient limbs disposed in saidgroovesand connections between said limbs, said limbs being embraced bythe walls of said grooves so as to transmit the torque independently ofsaid connections. 7 A flexible coupling comprising a pair of couplingelements, torque transmitting means comprising a series of transverselresilient limbs connected at their ends to orm a grid-likeinterconnecting member, and individual limb receiving recesses in eachof said elements.

8. A flexible shaft coupling comprising a air of coupling elementsarranged side by si e on the driving and driven shafts, a

grid-like member com rising a series of ture.

JAMES BIBBY.

